1. Technical Field
The present invention relates to a method of controlling a printing device, and to a printing device that is controlled by this control method.
2. Related Art
Keeping the recording paper in contact with the platen surface that determines the printing position on the recording paper, and maintaining a highly precise platen gap, are essential to maintain print quality in printers that print on recording paper by ejecting ink droplets from an ink ejection head (printhead). Suction platens that hold the recording paper to the platen surface by means of suction while the recording paper is conveyed are therefore used in order to convey the recording paper in contact with the platen surface. But if the suction pressure is low, the recording paper may lift away from the platen surface and print quality may drop, or the recording paper may brush against the printhead and be soiled by the ink.
To address this problem, Japanese Unexamined Patent Appl. Pub. JP-A-2010-201683 discloses a printing device having a first suction area that is sectioned into a grid formed substantially in the middle of the platen width, which is perpendicular to the conveyance direction of the recording paper, and a second suction area formed on both sides of the first suction area. The first suction area has first suction holes formed in the bottoms of the grid chambers, and the second suction area has second suction holes that are shaped or arranged differently from the first suction holes in the first suction area. The first suction area is used primarily to hold narrow recording paper to the platen, and the first and second suction areas are used together to hold wide recording paper to the platen.
A problem with the printing device disclosed in JP-A-2010-201683 is that the suction holes outside the recording paper are also open and air flows therethrough even when narrow recording paper is used. Suction pressure is therefore lost, and sufficient suction cannot be achieved.
In addition, if there are suction holes not covered by the leading end of the recording paper, ink or other fluid droplets may be scattered by the suction current, and good print quality cannot be achieved.